NK80-35-XL bearing: complete specifications & equivalents

The NK80-35-XL is a ISO 15 radial bearing sized 80 x 95 x 35 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.

Bearing dimension schematic Front view shows outer diameter D and bore d; side section shows width B. D = 95 mm d = 80 B = 35 mm side section front view
Principal dimensions: bore d 80 mm, outer diameter D 95 mm, width B 35 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand FAG
Bore diameter d 80 mm
Outer diameter D 95 mm
Width B 35 mm
Material GCr15
Seal / shield open
Internal clearance CN
Tolerance class P0
Cage steel
Basic dynamic load rating C 89 kN
Basic static load rating C0 184 kN
Fatigue load limit Pu 33 kN
Reference speed (thermal) 3650 rpm
Limiting speed (mechanical) 5800 rpm
Operating temperature -40 to +120 °C
Mass 425 g
Manufacturer designation NK80/35-XL
Standard ISO 15
Catalog version HR1 2026-09-25
Last verified 2026-09-30

Source: catalog reference (HR1 2026-09-25) · extracted 2026-09-30

Parameters extracted from the official FAG Rolling Bearings catalogue (HR1 2026-09-25); FAG® is a trademark of Schaeffler Technologies AG & Co. KG, used here for identification only — mpnbase is not an authorized FAG/Schaeffler distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at schaeffler.com.

Dimensions in inches & nk-series range

Bore d 3.15 in
Outer diameter D 3.74 in
Width B 1.378 in
ISO bore code —
Radial section height (D−d)/2 7.5 mm
Smallest bore in nk-series 5 mm
Largest outer diameter in nk-series 130 mm
Width range across nk-series 10–40 mm
Bore position in nk-series (smallest first) 40 of 46
Bore above smallest nk-series size 75 mm

Cross references & equivalents

Equivalent modelBrandMatch levelNote
NK80-25 SKF verify
Commonly quoted cross reference; confirm against the target catalog before ordering.
Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue.
NK80-35 SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 80×95×35 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting.

Interchange levels: full standard interchange · partial verify parameters · verify manual confirmation required. Links resolve to the equivalent model's specification page where available.

How the NK80-35-XL model number is decoded

envelope 80×95×35 mm: 80 mm seat is the hardened and ground shaft journal itself — there is no inner ring, with a thin 7.5 mm radial section packed with small-diameter needle rollers C is 89 kN and C0 184 kN at the 80 mm seat; the C/C0 ratio of 0.48 is characteristic of a needle bearing — high static rating relative to dynamic in a compact 95 mm outside diameter the fatigue load limit Cur is 33 kN, the limiting speed 5,800 r/min and the thermal reference speed 3,650 r/min; for small needle bearings the reference speed can exceed the kinematic limit, so the lower of the two governs the application dynamic capacity per millimetre of bore is 1.11 kN/mm and per millimetre of width 2.54 kN/mm — the reason 35 mm-wide needle bearings routinely replace much larger ball or roller positions mass is 425 g, just 0.13 g per mm² of projected 95×35 mm envelope, which keeps unbalanced forces low in fast-actuating linkages with a 80 mm bore this is a heavy-industrial bearing: 425 g of stiff ring and roller set, specified where rigidity matters more than speed The hardness requirement is unforgiving: below about 58 HRC the 80 mm journal brinels under the 184 kN static rating, and roughness above raceway finish accelerates roller wear Omitting the inner ring frees radial space — at a 80 mm shaft the outer diameter is only 95 mm and the width 35 mm, yet C is 89 kN The -XL suffix marks the X-life execution: refined raceway topography and upgraded materials lift the basic ratings versus the non-X-life bearing at the same 80×95×35 mm envelope. Typical applications include hydraulic and pneumatic pump eccentrics, copying and printing machine mechanisms and agricultural machine pivots and linkages, where the 95 mm outside diameter and 89 kN dynamic rating match the duty. In hydraulic and pneumatic pump eccentrics the unit fits a compact 80 mm seat, and in copying and printing machine mechanisms the 425 g mass keeps unbalanced forces low in fast linkages. Designers also specify it for agricultural machine pivots and linkages, relying on the 35 mm width and the published 184 kN static rating. Keep the specified radial clearance; an oversized shaft or heavy interference removes it and the needles bind hot immediately. On reciprocating duty ensure the stroke rotates the full needle set, or brinelling occurs at the same roller positions.

Typical equipment & failure modes

Common applications

  • two-stroke and compressor piston pins
  • agricultural machine pivots and linkages
  • rocker arms and valve trains
  • small electric motor accessory drives

Known failure patterns

  • journal brinelling when a no-inner-ring bearing runs on a shaft hardened below 58 HRC or finished too rough
  • needle skewing and jamming after momentary unloading of a flangeless (RNAO/NAO) pack
  • raceway pitting from contamination drawn through the open ends of an unsealed bearing
  • edge loading at the roller ends from a tapered or lobed shaft seat
  • cage damage from shock loading or from pressing the bearing through the wrong ring
  • lubricant starvation on fast reciprocating strokes that never fully rotate the needles
  • false brinelling during stationary transport vibration
  • spalling from excessive interference that removes the radial clearance
  • roller wear from misaligned connecting-rod eyes and rocker bores

Selection pitfalls — read before you substitute

  • Keep the specified radial clearance; an oversized shaft or heavy interference removes it and the needles bind hot immediately.
  • On reciprocating duty ensure the stroke rotates the full needle set, or brinelling occurs at the same roller positions.
  • Needle bearings are pure-radial units — any thrust must be taken by separate washers or an adjacent bearing, especially on flangeless RNAO/NAO.

Frequently asked questions

What are the dimensions of the NK80/35-XL?

The NK80/35-XL is a NK machined-ring needle roller bearing without inner ring with 95 mm outside diameter, 80 mm bore and 35 mm width, envelope 80×95×35 mm. Mass is 425 g.

What does the NK80/35-XL designation mean in the FAG/INA HR1 catalogue?

NK80/35-XL identifies this NK machined-ring needle roller bearing without inner ring in the Schaeffler HR1 rolling bearings catalogue; the -XL suffix marks the X-life execution. The envelope is 80×95×35 mm and the catalogue ratings are C 89 kN, C0 184 kN, Cur 33 kN.

What is the load capacity of the NK80/35-XL?

The basic dynamic load rating C is 89 kN and the basic static load rating C0 is 184 kN; the fatigue load limit Cur is 33 kN.

What is the maximum speed of the NK80/35-XL?

The limiting speed is 5,800 r/min and the thermal reference speed is 3,650 r/min. In the Schaeffler catalogue the reference speed is the thermally permissible running speed under defined load; the lower of the two values governs each application.

Can the NK80/35-XL run directly on an ordinary shaft?

Not on a soft shaft. The NK80/35-XL has no inner ring, so the 80 mm journal itself is the raceway: harden it to 58–64 HRC and finish-grind to the catalogue journal tolerance. Where the shaft cannot be hardened, use the corresponding with-inner-ring execution instead.

Reviewed & verified by the MPN Base engineering desk against source catalog HR1 2026-09-25 on 2026-09-30. Read our editorial & correction policy.